Costa Rica's Turrialba Volcano Erupts, Alert
Declared
The 3,340-meter (11,000-foot ) Turrialba
volcano, situated in the Cartago province,
53 kilometres east of the capital city San
José, last active in the 19th century
erupted on Tuesday, spewing ash and steam
and prompting authorities to evacuate a
small number of people from its slopes.

The Turrialba had shown increased activity
since the weekend, Vanessa Rosales,
president of Costa Rica's Comisión Nacional
de Emergencias (CNE) - national
emergency commission.

The area around the volcano is not very
populated, although ash from the volcano
could reach San José is activity at the
volcano intensifies and becomes more severe.

Authorities evacuated 20 people from its
slopes, with 30 more to be evacuated on
Wednesday, according to the CNE.

The volcano is not near any major coffee
production areas, though the town of
Turrialba and surrounding area has many
coffee plantations.

The Turrialba volcano has been dormant since
a 22 year active period that began in 1864,
according to Juan Segura, the director of
the Observatorio Vulcanológico y Sismológico
de Costa Rica (OVSICORI) - the Costa Rican
Volcanology and Seismology Observatory.

Ash from Turrialba's last major eruption in
February 1866 fell hundreds of kilometers
away, reaching Nicaragua, according to the
observatory.

On Christmas Day the Poás Volcano had a "phreatic
eruption", showing off for the dozens of
tourists, both national and foreigners, with
the expulsion of a vapour, water and
sediment from the centre of the crater's
lagoon. The column of vapour reached some
600 metres from the volcano.

The Poás is situated nortwest of San José,
minutes from the Juan Santamaría (San José)
international airport.

According to Wikipedia, a phreatic eruption,
also called a phreatic explosion or
ultravulcanian eruption, occurs when rising
magma makes contact with ground or surface
water. The extreme temperature of the magma
(anywhere from 600 to 1,170 °C (1,112 to
2,138 °F)) causes near-instantaneous
evaporation to steam resulting in an
explosion of steam, water, ash, rock, and
volcanic bombs. At Mount St. Helens hundreds
of steam explosions preceded a 1980 plinian
eruption of the volcano. A less intense
geothermal event may result in a mud
volcano. In 1949, Thomas Jaggar described
this type of activity as a steam-blast
eruption.

Turrialba, Costa RicaTurrialba is described as a quiet town, with its charming street corners and gorgeous surrounding sceneries is among the few places in Costa Rica with direct access to a volcano’s crater. From the summit of the volcano, you can on a clear day, see the Irazu, Poás and Barva volcanoes in the distance.

Among the most rarely visited national parks in Costa Rica, the Turrialba Volcano National Park is home of the active Turrialba Volcano, whose last major eruption occurred in 1866. The volcano itself is only 15 km northwest of town.

However, it is safe to climb, and though the facilities at the park are rather meager, it is still a worthwhile trip.

Turrialba is also famous for baseball. This is because Rawlings baseballs that are used in Major League games are manufactured in this tiny town.